INFR: Complete adoption of the QEP-2 standard label set

Problem

Repository labels diverge from the standard defined in QEP-2 (QuantEcon/qeps#2). As a software repository, QuantEcon.py takes the core 19 labels plus the software extension refactor — 20 labels.

The July 2026 tech-debt campaign created the labels it needed early (infrastructure, low-priority, security, good first issue, duplicate, wontfix) and renamed high priority → high-priority in place, so part of the standard set is now present. Remaining divergences:

Worth noting as a validation of the standard: refactor was already in active use here before QEP-2 — the label QEP-2 defines as the software extension is the one this repository independently reached for.

Sequencing

QEP-2 is Draft with a pilot-first adoption plan. This issue completes the alignment once the rollout reaches software repositories: run qe gh labels sync (additive; renames known variants in place so no history is lost), then a separate, deliberate qe gh labels prune pass reviewing each non-standard label one at a time.

Acceptance criteria

• Full sync applied once QEP-2 is Accepted and the rollout reaches software repos; all 20 labels present with standard colours and descriptions
• Each non-standard label reviewed individually under prune, with the decision recorded
• Existing issues re-labelled to exactly one Type each (overlaps with the backlog-triage issue)
• Any friction found is fed back to the QEP-2 thread as a field report

From the July 2026 technical-debt audit (AI-assisted; claims verified against 28d4b3b on 2026-07-25).

Start by reading QEP-2 and reviewing the repository's current labels against the listed 20-label standard. After QEP-2 is accepted and rollout reaches software repositories, run qe gh labels sync, then review each non-standard label with a separate qe gh labels prune pass. Done means the standard labels are present, each non-standard label has a recorded decision, issues have one Type, and friction is reported to the QEP-2 thread.